Conventional viral cultures and shell vial assay for diagnosis of apparently culture-negativeCoxiella burnetii endocarditis

A patient with culture-negative endocarditis was diagnosed with Q fever endocarditis based on the results of serological tests and positive leukocyte cultures obtained using conventional viral cultures and the shell vial technique. This case report suggests that isolation ofCoxiella burnetii from blood may allow better diagnostic and therapeutical evaluation of patients with Q fever endocarditis. The use of both conventional and shell vial viral cultures is recommended for the isolation ofCoxiella burnetii from the blood of patients with apparently culture-negative endocarditis.     

Anaerobic bacteremia in a cancer center

Seventy-five episodes of clinically relevant anaerobic bacterial bacteremia observed in cancer patients were reviewed. Gastrointestinal (22.7%), hematological (22.7%) and female genital tract (18.6%) cancers were the most common underlying malignant diseases. Among 84 strains of strict anaerobic bacteria recovered in the 75 patients, gram-negative rods were isolated in 49 patients (58.3%), gram-positive rods in 29 patients (34.5%) and gram-positive cocci in 6 patients (8%). Bacteroides spp. and Clostridium spp. were the most frequent pathogens (85.7%). Twenty-one episodes of bacteremia were polymicrobial, aerobic gram-positive cocci being the most frequently associated pathogens. When identified, the primary sites were the gastrointestinal tract (40%), the female genital tract (17.3%), skin and soft tissue (14.6%), the oropharynx (12%) and the lower respiratory tract (6.7%). The source remained unknown in 7 cases (9.3%). The overall survival (evaluated 10 days after the occurrence of bacteremia) was 82.5%. There was no difference in mortality between patients with monomicrobial and polymicrobial bacteremia. Pulmonary complications were more frequent in patients with fatal outcome in comparison to patients who survived. The mortality rate of the patients adequately treated was 10.3% compared to 41% for the patients not treated or treated inadequately (P=0.016, X₂).     

Susceptibility to multiple sclerosis mediated by HLA-DRB1 is influenced by a second gene telomeric of the TNF cluster

Susceptibility to multiple sclerosis (MS) is clearly associated with human leukocyte antigen (HLA)-DRB1*1501, but some studies show associations with HLA-B7 and -B18. These are often co-expressed with DRB1*1501 in the ancestral haplotypes (AH) denoted 7.1 (HLA-A3, B7, tumor necrosis factor [TNF]a11b4, DRB1*1501) and 18.1 (HLA-A25, B18, TNFa10b4, DRB1*1501). Here we present a systematic study of 218 patients and 274 controls typed at all standard class II and TNF microsatellite loci, and a novel non-synonymous polymorphism in the central major histocompatibility complex gene, inhibitor of κ B-like protein (IKBL). The C allele at IKBL+738 is only found on the 7.1 haplotype. HLA-DRB1*1501 was associated with disease, as expected. When subjects expressing DRB1*1501 were analyzed separately, TNFa11b4 and IKBL+738C were less common in the patients and, hence, mark an allele that mediates resistance which lies telomeric of IKBL.

TNFa10b4 and TNFa1b5 were more common in DRB1*1501 patients than in controls. These alleles have been associated with the 18.1 and 18.2 AH, respectively. Since no component of these haplotypes was an independent risk factor in this study, it appears likely that a gene linked to TNFa10b4 and TNFa1b5 modifies the effect of the susceptibility locus marked by HLA-DRB1*1501. Potential candidate genes telomeric of the TNF cluster are discussed.     

Interleukin-10 haplotypes in Celiac Disease in the Spanish population

Background  

Celiac disease (CD) is a chronic disorder characterized by a pathological inflammatory response after exposure to gluten in genetically susceptible individuals. The HLA complex accounts for less than half of the genetic component of the disease, and additional genes must be implicated. Interleukin-10 (IL-10) is an important regulator of mucosal immunity, and several reports have described alterations of IL-10 levels in celiac patients. The IL-10 gene is located on chromosome 1, and its promoter carries several single nucleotide polymorphisms (SNPs) and microsatellites which have been associated to production levels. Our aim was to study the role of those polymorphisms in susceptibility to CD in our population.     

Prevalence and risk factors of tinea unguium and tinea pedis in the general population in Spain

This study prospectively evaluated the prevalence and risk factors of tinea unguium and tinea pedis in the general adult population in Madrid, Spain. One thousand subjects were clinically examined, and samples of nails and scales from the interdigital spaces of the feet were taken from those patients presenting with signs or symptoms of onychomycosis and/or tinea pedis, respectively. In addition, a sample from the fourth interdigital space of both feet was collected from all individuals with a piece of sterilized wool carpet. Tinea unguium was defined as a positive direct examination with potassium hydroxide and culture of the etiological agent from subjects with clinically abnormal nails. Patients with positive dermatophyte cultures of foot specimens were considered to have tinea pedis. The prevalence of tinea unguium was 2.8% (4.0% for men and 1.7% for women), and the prevalence of tinea pedis was 2.9% (4.2% for men and 1.7% for women). The etiological agents of tinea unguium were identified as Trichopyton rubrum (82.1%), followed by Trichopyton mentagrophytes var. interdigitale (14.3%) and Trichopyton tonsurans (3.5%). Trichophyton rubrum (44.8%) and Trichophyton mentagrophytes (44.8%), followed by Epidermophyton floccosum (7%) and T. tonsurans (3.4%), were the organisms isolated from patients with tinea pedis. The percentage of subjects who suffered simultaneously from both diseases was 1.1% (1.7% for men and 0.6% for women). In a multivariate logistic regression analysis, age (relative risk [RR], 1.03) and gender (RR, 2.50) were independent risk factors for tinea unguium, while only gender (RR, 2.65) was predictive for the occurrence of tinea pedis. In both analyses, the presence of one of the two conditions was associated with a higher risk for the appearance of the other disease (RR, >25).     

Histones interact with anionic phospholipids with high avidity; its relevance for the binding of histone-antihistone immune complexes.

Antibodies recognizing anionic phospholipids have been described in systemic lupus erythematosus (SLE) and other autoimmune diseases. Recent studies have shown that some of these antibodies may recognize a cardiolipin-binding protein (apolipoprotein H) rather than phospholipids. A similar possibility is conceivable for other cardiolipin-binding proteins that are targets of autoantibodies. In this study we have addressed whether this might be the case for histones, a set of highly cationic and widely distributed proteins that react in a well known autoantibody system. Our results indicate that: (i) histones bind to anionic phospholipids (cardiolipin and phosphatidylserine) with high avidity, but not to zwitterionic phospholipids (phosphatidylcholine); (ii) monoclonal and polyclonal antihistone antibodies recognize histones bound to cardiolipin; (iii) the addition of histones to serum samples containing antihistone antibodies often enhances their anticardiolipin reactivity. In addition, we have found that antihistone-producing hybridomas derived from MRL-lpr mice may show anticardiolipin activity due to the presence of histones in the cell culture supernatants with the resultant formation of immune complexes. Taken together, the results suggest a potential role for histones in the anti-cardiolipin activity detected in sera containing antihistone antibodies. These histone-phospholipid interactions should be taken into account when evaluating the pathogenic effects of antihistone antibodies or other autoantibodies reacting with nuclear components (e.g. nucleosomes) containing histones.     

Establishment and characterization of a continuous human chondrosarcoma cell line,ch-2879: comparative histologic and genetic studies with its tumor of origin

Chondrosarcomas are malignant cartilage-forming tumors that represent the second most common malignant solid tumor of bone. These biologically poorly understood neoplasms vary considerably in clinical presentation and biologic behavior. Chemotherapy and radiation therapy are generally ineffective. Here we describe the establishment and characterization of a new human chondrosarcoma cell line named ch-2879, and we compare the cell line with its tumor of origin. The cell line was established from a recurrent grade 3 chondrosarcoma of the chest wall and characterized by growth kinetics and morphologic studies. Immunocytochemistry and RT-PCR were performed to examine the expression of cartilage-specific phenotypes. Genetic characterization was performed using cytogenetics, fluorescence in situ hybridization, flow cytometry, and molecular techniques for analysis of the genes implicated in cell cycle control, amplification of MDM2, CDK4, and Cyclin D1, and mutations in the p53 gene. ch-2879 cells were subcultured for more than 80 passages. They expressed vimentin, HNK-1, HBA-71, Ki-67, cyclin D1, Fli-1, S-100, p21, p27, and p53 and were negative for cytokeratin, EMA, p14, p16, MDM2, Rb, and c-erb-b2 antigens. Cytogenetically the recurrent tumor showed a hyperhaploid karyotype with clonal numerical and structural abnormalities. The sole structural abnormality was a chromosome derivative of a t(1;21) translocation. The cell line at passage 3 showed two populations: the hyperhaploid and an exactly duplicated, hypotriploid population. After the 18th passage, only the hypotriploid population was present. The cells expressed collagen 2. Molecular comparison of the primary and recurrent tumor evidenced an in vivo molecular change consisting of a deletion of 9p21 genes in the recurrence, probably caused by a selection process. Because of its gene expression profile, including expression of genes implicated in chondrogenesis in uncoated plastic dishes, this cell line may prove useful for cellular and molecular studies as well as studies of chondrosarcoma characterization and treatment.     

Contribution of HLA class II genes to susceptibility in achalasia

Abstract: Achalasia is a motor disorder of the esophagus resulting in functional obstruction. The cause of the lesion is unknown although genetic and immunologic factors have been suggested. An association with serological HLA epitopes has been previously reported. In this study, we have further examined this HLA class II association with susceptibility to achalasia by DNA based methods. Achalasia patients ( n =40) and healthy controls ( n = 275), all Caucasians and unrelated, were included in the analysis. The strongest associations were with HLA-DQAl*0101 and two HLA-DQαβ heterodimers having their a chain encoded by this allele. Moreover, relative risk was significantly higher in DQAl*0101 homozygotes as compared to heterozygotes and results suggested that DQB1*02 may have a protective role.